Soehardjoepri (2004) “Aplikasi Analisa Multivariate dan Analisa Regresi Linier Berganda pada Proses Pengolahan Air Minum”, Limits: Journal of Mathematics and Its Applications, 1(2), p. 41. vailable at: https://journal.its.ac.id/index.php/limits/article/view/5278 (ccessed: 6December2025).